Dielectric Function of a Metal-Organic Molecule

 
Here is a curve of a dielectric function taken from a random scientific paper.
Epsilon from experiment
The material is some kind of metal-organic molecule; shown in the inset.
The real part (e') and the imaginary part (e'') as measured in a small range of frequencies (expressed as photon energy) is shown.
While the general structure clearly shows the effect of (a strongly damped) oscillation mechanism, there is some fine structure visible. This is easily understood in principle, because all kinds of oscillations are possible in contrast to the simple model with only one oscillating atom.
 

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go to 3.3.4 Complete Frequency Dependence of a Material

© H. Föll (Advanced Materials B, part 1 - script)